The eldest son of North Korea's late leader Kim Jong-Il has arrived in Beijing as Pyongyang prepares a state funeral for his father, South Korea's Yonhap news agency reported today.

The eldest son of North Korea's late leader Kim Jong-Il has arrived in Beijing as Pyongyang prepares a state funeral for his father, South Korea's Yonhap news agency reported on Monday.

Citing what it called a source familiar with Kim Jong-Nam's activities, it said he arrived in Beijing from Macau a few days ago and "has been placed under Chinese protection".

Seoul's National Intelligence Service said it had no information on the report and there was no other confirmation.

It was not clear whether the son would attend Wednesday's funeral in Pyongyang, Yonhap said.

Kim Jong-Nam, 40, has lived abroad -- mainly in the Chinese territory of Macau -- for years after apparently falling out of favour with his father for trying to enter Japan on a false passport in 2001.

Kim Jong-Il eventually backed his youngest son from another marriage as the next ruler. The North proclaimed Kim Jong-Un the "great successor" after his father died of a heart attack on December 17.

Kim Jong-Nam's whereabouts have been the subject of intense speculation since his father's death.

"He's moving here and there. It has been hard to track him down," said Ricardo Pinto, publisher of Macau Closer magazine.

"It appears that he lives at his house sometimes, and sometimes he stays at different hotels."

In a January interview with the Tokyo Shimbun, Jong-Nam was quoted as voicing opposition to the planned dynastic succession.

"Even Chairman Mao Zedong of China did not enforce hereditary succession," he was quoted as saying.

"(Hereditary succession) does not fit with socialism, and my father was against it as well."